Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
69 Cards in this Set
- Front
- Back
|
Smooth ER
|
-membrane bound, interconnected channels
-Found in Cardiac and Skeletal Muscle--> Sarcoplasmic Ret. -Extensive in cells producing steroids and lipids (liver and adrenal cortical cells) -Contain Enzymes to make cholesterol -Calcium Reservoir |
|
|
Smooth ER carries out steps in _____ and _____ _____.
|
-Glycogen and Lipid Metabolism
|
|
|
Enzymes (Smooth ER)
|
-makes cholesterol
-Systems inactivate hormones and detox of drugs |
|
|
Mitochondria
|
-Double unit Membrane bound provides energy
-Specialized compartments inside -Cristae: ^innter membrane surface area |
|
|
Reactions of Mitochondria
|
-Tricarboxylic Acid Cycle
-ATP Synthesis -Lipid Metabolism |
|
|
Cytoskeleton
|
-Structural proteins involved with cell shape and organelle movement
-3 Classes: Microtubles, Microfilaments, Intermediate filaments |
|
|
Microtubules
|
-tubular (25nm diameter=thickest)
-Made up of Alpha and Beta tubulin -Associated with microtubules-associated proteins (MAPs) --> needed for microtubule fxn |
|
|
Microtubles: Role in Intracellular Transport and Structure
|
*Movement depends on molecular motors
-Centrioles-->2=centrosome -Cilia (9+2 arrangement in basal body): wave-like in ovaries -Flagella: whip-like=only in sperm |
|
|
Microfilaments (Actin Filaments)
|
-thin (7nm)
-made up of actin (network=physical support and attachment pts) -Ex: Actin binds to myosin in contractile cells |
|
|
Intermediate Filaments
|
-fiber-like (10nm)
-Include: keratins (epithelial cells), vimentin (connective tissue), desmin (muscle), neurofilaments (neurons), glial fibrillary acidic protein (glia) |
|
|
Smooth ER
|
-membrane bound, interconnected channels
-Found in Cardiac and Skeletal Muscle--> Sarcoplasmic Ret. -Extensive in cells producing steroids and lipids (liver and adrenal cortical cells) -Contain Enzymes to make cholesterol -Calcium Reservoir |
|
|
Smooth ER carries out steps in _____ and _____ _____.
|
-Glycogen and Lipid Metabolism
|
|
|
Enzymes (Smooth ER)
|
-makes cholesterol
-Systems inactivate hormones and detox of drugs |
|
|
Mitochondria
|
-Double unit Membrane bound provides energy
-Specialized compartments inside -Cristae: ^innter membrane surface area |
|
|
Reactions of Mitochondria
|
-Tricarboxylic Acid Cycle
-ATP Synthesis -Lipid Metabolism |
|
|
Cytoskeleton
|
-Structural proteins involved with cell shape and organelle movement
-3 Classes: Microtubles, Microfilaments, Intermediate filaments |
|
|
Microtubules
|
-tubular (25nm diameter=thickest)
-Made up of Alpha and Beta tubulin -Associated with microtubules-associated proteins (MAPs) --> needed for microtubule fxn |
|
|
Microtubles: Role in Intracellular Transport and Structure
|
*Movement depends on molecular motors
-Centrioles-->2=centrosome -Cilia (9+2 arrangement in basal body): wave-like in ovaries -Flagella: whip-like=only in sperm |
|
|
Microfilaments (Actin Filaments)
|
-thin (7nm)
-made up of actin (network=physical support and attachment pts) -Ex: Actin binds to myosin in contractile cells |
|
|
Intermediate Filaments
|
-fiber-like (10nm)
-Include: keratins (epithelial cells), vimentin (connective tissue), desmin (muscle), neurofilaments (neurons), glial fibrillary acidic protein (glia) |
|
|
Nucleus
|
-contains genetic info=chromatin
-2 kinds: Heterochromatin, Euchromatin |
|
|
Heterochromatin
|
-condensed DNA that is not being translated
|
|
|
Euchromatin
|
-more loosely organized chromatin that is being transcribed
-Level of Cellular Activity= amt of euchromatin vs heterchromatin |
|
|
Nucleolus
|
-Darkly stained spherical structure composed of RNA and protein
-Synthesis of Ribosomes |
|
|
Nuclear Envelope
|
-Double membrane with nuclear pores (mRNA moves from nucleus--> cytoplasm to direct protein synthesis)
|
|
|
Cell Cycle Phases
|
-2 Principle Phases: Interphase and Mitosis
|
|
|
Interphase
|
-Phase between separate episodes of mitosis
-Cell growth -Phases: G1, S, and G2 -NOT STAGE OF MITOSIS |
|
|
A) G1 Phase (Interphase) and
B) S Phase |
A-Gap or Growth
B-DNA Synthesis |
|
|
Mitosis
|
-follows S and G2 Phases
-4 Stages: PMAT |
|
|
Diverse Rate of Cell Division Examples (Mitosis)
|
-Labile Cells
-Stable -Permanent |
|
|
Labile Cells-Cell Division Rates
|
-Never go to G0, divide rapidly with a short G1
-Ex: Bone marrow, gut epithelium, skin and hair follicle |
|
|
Stable (Quiescent Cells)-Cell Division Rates
|
-Enter G1 from G0 when stimulated
-Ex: Hepatocytes, Lymphcytes |
|
|
Permanent Cells-Rate of Cell Divison
|
-Remain in G0 and never divide; regenerate from stem cells
-Ex: neurons, skeletal and cardiac muscle cells, RBCs |
|
|
Mitosis vs Meiosis
|
*Mitosis
-Same as parent cell -undertaken by somatic cells *Meiosis -occur in gonads -Produces sex cells -Results in haploid cells (23 chromosomes) |
|
|
Cell Death (2 types)
|
-Necrosis
-Apoptosis |
|
|
Necrosis
|
-accidental cell death
-results from acute cell injury and damage to the plasma membrane -can be caused by environment -"Messy" form of cell death=INFLAMMATION |
|
|
Apoptosis
|
-programmed cell death
-NO INFLAMMATION -occurs under normal condn -Regulated -"Tidy" form of cell death (DNA fragmentation, cell shrinkage, membrane blebbing) |
|
|
Composition of Cell (4)
|
-Proteins
-Carbohydrates -Lipids -Nucleic Acids (all organized into membranes and organelles in aqueous environment) |
|
|
Eukaryotic Cells are bounded by ______ which encloses ______.
|
-Plasma Membrane
-Cytoplasm containing cellular organelles and inclusions |
|
|
Most cells consist of nucleus bounded by ______, _______, ________.
|
-Nuclear envelope
-Double membrane enclosing genetic material (chromatin) |
|
|
Cell ______ and ______ of organelles can reflect the fxn of highly specialized cells
|
structure and arrangement
|
|
|
Specific Fxns of Plasma Membrane
|
-Enclose and define the extent of cell
-Form a semipermeable barrier b/w the cell and the extracellular environment -Interact ion b/w cells |
|
|
Fxns of Membrane Proteins (5)
|
-Membrane Channels
-Transporters -Receptors -Celle Surface Makers -Adhesion Molecule |
|
|
Membrane Carbohydrates
|
-Glycoproteins and Glycolipids (Glycocalyx)
*Impt in cell recognition |
|
|
_________ is interspersed between fatty acids tails and influences membrane fluidity (as does saturation of f.a. tails)
|
Cholesterol
|
|
|
Membrane Proteins embedded in lipid bilayer
|
-Integral proteins (transmembrane)
|
|
|
Membrane Proteins: Peripheral Proteins
|
-Anchored to the outer or inner leaflet without traversing the membrane
|
|
|
Fluid Mosaic Model
|
Proteins and lipids can move laterally within each layer
|
|
|
Roles of Membrane Proteins: Membrane Receptors
|
-For hormones immunoglobins and other signaling molecules allow cells to respond to signals for other cells
-Ex: integrins allow cells to interact with extracellular matrix and endocytosis: other receptors allow this |
|
|
Ion Channels
|
-Allow ions and aqueous sol'n to diffuse across the membrane Decrease a conc'n gradient
|
|
|
Water Channels (Aquaporins)
|
-Allow water to move across certain water-permable membranes by osmosis (ex: kidney tubules)
-Usually regulated by hormones |
|
|
Membrane Pumps (Roles of Membrane Proteins)
|
-Allow substances to move against a conc'n or electrochemical gradient by active transport
|
|
|
Lipid Bilayer is permeable to...
Impermeable to... |
*Permeable
-Oxygen, CO2, Steroids *Impermeable -Glucose |
|
|
Passive Processes (Membrane Permeability) and Examples
|
-Transport=No energy needed (uses kinetic energy of ind'l molecules or ions)
-Ex: Osmosis, Simple Diffusion, Channel-Mediated facilitated diffusion and carrier mediated facilitated diffusion |
|
|
Active Processes (Membrane Permeability)
|
-Cell uses energy (ATP breakdown)
-Moves against conc'n gradient |
|
|
Active Transport (Active Processes)
|
-Solutes transported across plasma membrane with use of energy
-Higher to lower conc'n -Use enzymes and carrier proteins |
|
|
Transport in Vesicles (Active Processes=Membrane Permeability)
|
-Endocytosis
-Pinocytosis (Drink) -Phagocytosis (Eat) -Receptor-Mediated Endocytosis: involves formation of coated vesicles coated w/ clathrin protein -Exocytosis |
|
|
Exocytosis Examples
|
-Release neurotransmitters
-Hormones (Endocrine Cells) -Digestive Enzymes |
|
|
Ribosomes
-Def -They play a key role in _____ _____ by forming peptide bonds b/w ______ _________. |
-Multimolecular compleses of protein and nucleic acid
-Protein synthesis -Amino Acids |
|
|
mRNA
|
-Ribosomes attach
-Contains code for sequence of AA in protein undergoing synthesis |
|
|
tRNA
|
-Binds indirectly= 2nd ribosomal subunit catalyzes AA to form peptide bond
|
|
|
Polyribosome
|
-Ribosomes are associated into bead-like chains for synthesis of proteins
~Free: Synthesize cytoplasmic structural proteins ~Bound (secreted) assoc. w/ RER |
|
|
Post-Translational Modification (RER)
|
-Add'n of oligosaccharides (Glycosylation) and removal of peptide fragments to proteins synthesized in RER
|
|
|
Modified proteins move from RER to Golgi to further _____ _____ and ________ into membrane bounded ________.
|
-Modification, sorting, and packaging
-Secretory Granules |
|
|
-Cis Face (Golgi)
|
=forming face
-receives newly synthesized proteins form the RER |
|
|
Trans (Golgi)
|
=maturing face
-gives rise to secretory vesicle containing concentrated modified, protein |
|
|
Lysosome
|
-undergo modification and sorting w/in specialized regions of the Golgi
-Contain hydrolytic enzymes -Outside=2destroy bacteria -Processing=lipoproteins (endocytosis) -Provide digestive enzymes 4 intracellular processing of endocytosed material |
|
|
Proteosomes
|
-No membranes
-Large protein complexes involved in processing of cell proteins that have been marked 4 regulated destruction by ubiquitination |
|
|
Perioxosomes
|
-smaller than lysosomes,
-containing enzymes that degrade hydrogen peroxide and fatty acids -detoxify several toxic substances such as alcohol |
